java实现下载附件功能

Posted 2022-08-23 爱米酱

前台js方法：

//下载为Excel
function downResult() 
    
      var url = $ctx/downResult.do;
      var fileName = "稽核结果.xlsx";
      var form = $("<form></form>").attr("action", url).attr("method", "post");
      form.append($("<input></input>").attr("type", "hidden").attr("name", "fileName").attr("value", fileName));
      form.appendTo(body).submit().remove();

后台controller方法(这里下载的类型是Excel，下载其他文件需要修改类型)：

@ResponseBody
    @RequestMapping(value="downResult.do")
    public ModelAndView downResult(HttpServletRequest request,
                              HttpServletResponse response)throws Exception
        
        URL url = getClass().getClassLoader().getResource("auditResult.xls");
        String path = url.getPath();
        //downloadFile(request,response, path, "auditResult.xlsx");
        down(request,response, path, "auditResult.xlsx");
        
        return null;
    

    private void down(HttpServletRequest request, HttpServletResponse response, String path,String fileName) throws Exception 
          java.io.BufferedInputStream bis = null;
          java.io.BufferedOutputStream bos = null;
          try 
           String agent = request.getHeader("User-Agent");
           boolean isMSIE = (agent != null && (agent.indexOf("MSIE") != -1 || agent.indexOf("Trident") != -1));

           if (isMSIE) 
            response.setHeader("Content-disposition",
              "attachment; filename=" + java.net.URLEncoder.encode(fileName, "UTF8"));
            else 
            response.setHeader("Content-disposition",
              "attachment; filename=" + new String(fileName.getBytes("utf-8"), "ISO8859-1"));
           
           response.setContentType("application/x-xls");

           
           bis = new java.io.BufferedInputStream(new java.io.FileInputStream(path));
           bos = new java.io.BufferedOutputStream(response.getOutputStream());
           byte[] buff = new byte[2048];
           int bytesRead;
           while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) 
            bos.write(buff, 0, bytesRead);
           
          catch(Exception e) 
           /*operResult.setResult("fail");
           operResult.setMsg("操作失败:"+e.getMessage());*/
              e.printStackTrace();
          finally 
           if (bis != null)
            bis.close();
           if (bos != null)
            bos.close();